$ { {-5} \times \left[\begin{array}{rrr}{0} & {1} & {-2} \\ {1} & {0} & {-2}\end{array}\right] = {?} } $
Explanation: To multiply a matrix by a number, multiply each item of the matrix by the number. ${\left[\begin{array}{rrr}{-5}\times{0} & {-5}\times{1} & {-5}\times{-2} \\ {-5}\times{1} & {-5}\times{0} & {-5}\times{-2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{0} & {-5} & {10} \\ {-5} & {0} & {10}\end{array}\right]}$